Drew Peterson's lawyer told the jury in his murder trial today that the woman he is accused of killing was bossy, lied, had a furious temper and went to therapy.

Lawyer Joel Brodsky, Peterson's lead defense attorney, attacked the character of Kathleen Savio, Peterson's third wife, in his opening statement. Brodsky's opening argument was interrupted by objections from prosecutors, just as the prosecutor's opening statement was marked by objections from Brodsky.

The contentious start to the trial foreshadows what is expected to be a battle over the prosecutor's key evidence: comments that Savio made to others before she died in 2004, and comments that Peterson's fourth wife Stacy Peterson made to people. Stacy Peterson has been missing since 2007.

Brodsky told the jury that Savio was on antidepressants and had been known to fly into jealous rages during the time that she and Peterson were divorcing in 2004. He described her as bossy and a liar, and said she would yell so loudly that other police officers where Peterson was a sergeant could her hear over the phone.

Savio was found dead in her bathtub one Monday morning in February that year, and her death was ruled an accidental fall by state police, Brodsky said. It had nothing to do with Peterson.

Peterson, 58, was charged with Savio's murder years later, after his fourth wife, Stacy Peterson, disappeared and Peterson became the focus of media attention and police investigators. Police exhumed Savio's body of as part of the investigation. A new forensic analysis performed on the body in 2007 showed that Savio did not die accidentally, but rather was murdered. Police then charged Peterson.

Brodsky said today that the only reason Savio's body was exhumed was the media's involvement in the case once Stacy disappeared. She has never been found.

Brodsky said that the defense would present forensic pathologists to testify that Savio's death was accidental. The prosecution will likely present its own expert witnesses to testify that it was homicide.

The defense's portrait of Peterson was in stark contrast to that presented by prosecutors just hours earlier, as they argued to the jury that Peterson stood to gain financially from Savio's death, and had the police knowledge to stage the crime scene to make it look like an accident. Peterson was a police sergeant in Bolingbrook, Ill., at the time of Savio's death.

"The evidence shows this wasn't an accident," prosecutor James Glasgow told the jury of seven women and five men. He noted that at the time of Savio's death, Peterson was financially supporting her, his girlfriend Stacy Peterson, two homes, and his children.

Both of the opening statements were interrupted frequently by objections from attorneys. Legal wrangling over what evidence could be mentioned during opening statements had plagued the trial since its start this morning, when Brodsky called for a mistrial within minutes of the prosecution's opening statement. Brodsky's request was denied.

The arguments over what the jury will be allowed to hear are expected to play a pivotal role in the case, as the prosecution tries to prove their murder charge by admitting statements Savio and Stacy Peterson made to acquaintances.

Judge Edward Burmilia has said he will rule on each issue as it comes up during trial.

The first witness to testify in the trial was the woman who found Savio dead in her bathtub in 2004.

Mary Pontrelli, a close friend and neighbor of Savio's, said that she knew Savio and Peterson had a rocky marriage that exploded when Savio discovered Peterson was cheating on her with another woman.

"She did find out he was cheating on her and she was very upset by that," Pontrelli said. "She did change the locks on the front door."

Savio also had a deadbolt installed on her bedroom door, a door which had a large hole in it when photographed by investigators after Savio's death, direct questioning of Pontrelli revealed.

Pontrelli described the Monday night when Drew Peterson came to her home and said he had not been able to reach Savio for 24 hours. He was trying to drop his children off at Savio's house after a weekend in his custody.

According to Pontrelli's testimony, Peterson and Pontrelli first contacted Savio's boyfriend and then a locksmith to get into SAvio's home to check on her. Once inside, Peterson waited downstairs and checked the garage for Savio's car while Pontrelli went upstairs and found Savio dead in her bathtub, her hair soaked in blood.

Peterson then came upstairs and took Savio's pulse, Pontrelli said. At some point in the night, Peterson told Pontrelli he was the beneficiary of Savio's will, Pontrelli said.

Defense attorneys, upon cross-examination, pointed out the Pontrelli had changed the details of her story in various accounts she gave to police, prosecutors, and grand juries. Pontrelli said she could not remember what she told police the night of the incident.